Neutral Grounding Resistors are used for resistance grounding of industrial power system. They are generally connected between ground and neutral of transformers, generators and grounding transformers. Neutral Grounding Resistors are used in order to limit maximum fault current to a value which will not damage the equipment in the power system, yet allow sufficient flow of fault current to operate protective relays to clear the fault. Although it is possible to limit fault currents with high resistance Neutral Grounding Resistors, phase to ground short circuit currents can be extremely reduced. As a result of this fact, protection devices may not sense the fault. Therefore, it is the most common application to limit single phase fault currents with low resistance Neutral Grounding Resistors.

FEATURES

Stainless-steel resistor elements

Current transformer included (EN 60044-1)

Bolted resistor element connections instead of welded connections in order to be able to assemble spare parts on site immediately

Typically, RAL 7032(and others) painted

Typically, 2 mm hot dip galvanized steel enclosure

High thermal capacity to absorb high currents

High altitude ratings

Custom made lifting eyes provide secure lifting

Rugged shock-resistant construction

Kian Tajhiz resistors are designed to absorb a large amount of energy without exceeding temperature limitations defined in IEEE 32. Neutral Grounding Resistors Kian Tajhiz can be used for indoor and outdoor and the neutral point is connected with a porcelain bushing or with a (minimum cross-section = 70 mm2 copper or 95 mm2 aluminum) high voltage (XLPE) cable from the bottom, top or side. The most common protection degree preferred for Neutral Grounding Resistors is IP 23 as it allows the resistor elements to cool easier and they can be used both at sea shores and deserts because the resistor elements are completely stainless steel and does not get affected by extreme conditions. Neutral Grounding Resistors are shipped with maintance and installation guidelines. In maintance and intallation guidelines, recommended relay settings for each Neutral Grounding Resistor are stated as well. Kian Tajhiz provides complete technical assistance in order to meet your specifications or site conditions.

TESTS

Routine Tests

Withstand test of dielectric strength at network frequency for one minute

Measurement of total DC resistance

Insulation test of resistor blocks

Galvanization thickness test

Paint thickness test

Type Tests(on demand)

Temperature rise test

Protection degree test

Impulse voltage test (1,2 / 50 µs)

Measurement of AC resistance

Seismic test

SELECTION DETAILS

System Voltage

Line to Neutral Voltage

Desired Current Rating

Desired Resistance Level

Maximum Time ON (seconds)

Bushing Entry or Cable Entry

Current Transformer Ratio (if applicable)

Disconnector Switch (if applicable)

Special Options (if applicable

ABOUT US

KIANTAJHIZ Co. has been located in east of Tehran province and has started its activities from 2002 in order to provide projects in the field of Gas, Oil, Petrochemical, and steel industries, as well as other primary and secondary industries with a complete package of electrical and electromechanical devices and machinery as its main objective. As well as, this company has been registered as an authorized supplier in the approval vendor list of ...